Air gun



y 22, 1952 H. A. YATES 2,604,361

AIR GUN Filed April 13, 1946 za [I E IZ 39 l 2 .1 I I0 34 F 35 E 17 70 x5 17 39 49 o n 39 45 /9 49 minimal IN V EN TOR. HARRY Maris ATTamex Patented July 22, 1952 UNITED STATES PATENT OFFICE AIR GUN Harry A. Yates, Bridgeport, Conn. Application April 13, 1946, Scrial No. 662,005

2 Claims. l

' The present invention relates to air guns, particularly of the type for use'in machine shops or other industrial plants for blowing chips, shavlugs, and the like, produced in such machines as lathes, drills, and the like, as well as for various other cleaning and blowing operations. The invention is an improvement over the safety air nozzle disclosed in my United States Letters Patent No. 2,320,964, granted June 1, 1943, which is adapted, in addition to providing a central cleaning air jet, to provide a protective shield of air in the form of a cone in surrounding relation to the central air jet, an object of the invention being to provide a combined'va-lve and nozzle structure, wherein the valve body is adapted to have the air jet means, for providing the central cleaning air jet, and the conical protective air shield, combined therewith in a simple and economical manner, and whereby an adequate supply of compressed air may be transmitted from the air hose'to the air jet and shield.

Another object is to provide an improved type of valve, adapted to be normally closed by the airpressure in the air line, and further to provide a readily removable and replaceable valve closure member.

A further object is to provide an improved nozzle structure, whereby extension tubes of varying lengths may be readily attached to the nozzle.

With the above and other objects in View an embodiment of the invention is shown inthe accompanying drawings, and this embodiment will be hereinafter more fully described with reference thereto, and the invention will be finally pointed out in the claims.

.In the drawings Fig. l isaside elevation of an air gun, according to the illustrated exemplary embodiment of the invention.

Fig. 2 is a rear elevation.

Fig. 3 is a top plan view.

Fig. lis a longitudinal vertical sectional view, taken along the line 4-4 of Fig. 3, and showing the valve in its closed position. f

\ Fig. 5 is a longitudinal vertical sectional view, partially in side elevation, showingthe valve in its open position.

' Fig. 6 is a transverse sectional view, taken along the line 6-5 of'Fig. 5. v

Fig. '7 is a View partially in side elevation and partially in vertical section, showing the two parts-of the valve stem in unassembled relation.

Fig. 8 is a vertical sectional view of the valve closure member.

Fig. 9 is a fragmentary longitudinal sectional view, showing a tubular extension attached to the nozzle.

Similar reference characters indicate corresponding parts throughout the several figures-of the drawings.

Referring to the drawings, the air gun, according .to the illustrated exemplary embodiment of the invention, comprises a body member ID having a forwardly extending cylindrical barrel portion I! and a rearwardly extending cylindrical hose attaching portion [2, the horizontal axis of the barrel portion I I being upwardly oifset with respect to the horizontal axis of the hose attaching portion. l2. The vertically extended intermediate portion of the body between the portions II and I2 is provided with a vertical opening therethrough, consisting of an upper valve stem bearing portion l3, an intermediate air passage portion 14, of larger diameter than the bearing portion I3, and a lower air chamber portion 5 of larger diameter than the intermediate air passage l4, the lower portion of the chamber l5 being provided with internal screw threads [8. The upper end of the chamber 15 is provided with an annular valve seat rib I! in surrounding relation to the lower end of the passage M, the outer. periphery of the rim being undercut, as at is.

The hose attaching extension i2 is provided with a threaded pocket [9 which communicates with the chamber I5 through a port 20. This port may be conveniently produced through the boring of the pocket is and the chamber l5 by employing a suitable tool which forms a centrally disposed projection ill in the base of the pocket is, the perimeters of the pocket and the chamber intersecting, so that in forming the two bores the port 28 is produced, the projection I8 being partially undercut through this operation so that it porvides an overhanging baifie in line with the valve seat rib ll, which in the closed position of the valve directs the flow or air away from the, valve seat and downwardly into the valvechamber 5. The compressed air supply hose is adapted to be attached to the air gun by a suitable nipple screwed into the pocket 19.

-The forwardly projecting barrel portion H is provided with a cylindrical bore 22 connected by a tapered passage 23 to the air passage l4, and is adapted to have the nozzle portion of the air gun secured therein, as will presently more fully appear. 7

The valve comprises. a valve stem or plunger 24 provided at its upper end with a stud portion 3 having a flange 26 at its base, the stud portion adapted to be engaged by a press fit with the socket 21 of the headed press-button 28, the press fit assembly of the stem with the press-button assembling these parts with the valve body. In the assembled relation, as shown in Figs. 4 and 5, the press-button is slidably fitted within the bearing portion 13 of the valve opening, and the flange 26 is slidable within the passage l4 and prevents upward disengagement of the valve stem. The head of the press-button prevents downward disengagement of the stem. The valve stem is provided at its lower end with a reduced diameter extension pin portion 29 for slidable engagement with the valve closure member.

The valve closure member 30 is provided with a downwardly extending stud portion 3| adapted to slidably fit within a pocket 32 provided in the flanged closure cap or plug 33 secured in the lower end of the chamber l5, a sealing gasket 34 being preferably provided between the flange of the cap and the lower end of the valve body. The upper end of the valve closure member is provided with a recess 35 in which a yieldable valve face member 36, of rubber or other suitable material, is engaged and secured by means of a flanged tubular eyelet member 3'! engaged with a press fit in a central hole 38 in the valve closure member. While the valve closure member is thus vertically aligned with the valve stem and is adapted to be operated by it, it may be conveniently removed and replaced, without disturbing the permanently assembled stem, simply by removing the closure cap 33.

In operation, the compressed air supplied by the hose to the air gun enters the chamber 15 and normally exerts pressure upon the valve closure member to seat it firmly against the valve seat I8 and thus normally maintainthe valve closed. In order to open the valve the press button is depressed, forcing the valve closure member downwardly to the position shown in Fig. 5, thus admitting air through the passage 14 to the passage 23 where it is directed through the nozzle, as will presently more fully appear. As soon as the press button is released the air entering the chamber I5 exerts pressure upon the under side of the valve closure member, which in its open position as shown in Fig. 5 is slightly raised from the upper end of the closure cap 33, and forces the valve closure member into closed position.

The nozzle member 39 is provided at its rearward end with a reduced diameter hub portion 40 provided uponits rearward portion with longitudinally extending radial ribs 4|, their forward ends being in rearwardly spaced relation to a conical shoulder portion 42, to provide between the ribs and the shoulder an annular air chamber 43. The conical shoulder 42 in the assembled relation of the nozzle is disposed in opposed relation to the forward end of the barrel portion H which is beveled, as at 44, to thus provide an annular converging slot 45 directed outwardly and downwardly from the annular air chamber 43. The ribs 4! are so dimensioned that their peripheral surfaces are adapted to be engaged with a forced press fit in the cylindrical pocket 22, the position of the nozzle being determined by abutment of its inner end with the conical passage 23 and the dimensions being so predetermined that this assembled position predetermines the opening of the slot 45. An axial passage 46 extends through the nozzle and is provided atitsouter endwith a reduced jet opening 41. Thus air directed through the valve passes into the passage 23 and is then divided so that a portion of it flows through the central bore 46 and is directed as a central air J'et through the jet opening 41, while the other portion flows through the passages of the ribs 4! to the annular chamber 43 and is directed through the slot 45 as a conical protective air shield in surrounding relation to the central air jet.

The protective air shield constitutes a shielding barrier extending from a point substantially above the end of the nozzle to a relatively large circular area of the table or other surface bein cleaned, the pressure of this protective shield being sufliciently great so that any chips flyin upwardly from the table, as the main air jet is played upon them, are prevented from penetrating the air shield, and therefore drop to the table surface, thus effectually protecting the worker's person and especially his eyes from flying chips. As the air shield confines the chips down to the table surface they are prevented from spreading laterally as well as upwardly.

While the central air jet opening 4! may be provided in the extreme outer end of the nozzle, it is preferably recessed within an internally threaded pocket extension 43 into which a threaded tip member 49 is screwed, this tip member being provided with a passage 50 of substantially larger diameter than the jet opening 41, so that it will not interfere with the jet of air being ejected therefrom. This tip is especially adapted for the attachment to the nozzle of an extension tube, and for this purpose the surface of the nozzle surrounding the jet opening 4'! is conically shaped, as at 5|, and the inner end of the tip is conically beveled, as at 52. As shown in Fig. 9 the extension tube 53, which may be of any desired length, is fitted within the opening 50 of the tip and its rearward end portion is slightly belled out, as at 54, against the conical surface 52 of the tip. Thereupon the tip is screwed into the pocket 48 and the belled out end 54 is clamped between the conical surfaces 5| and 52, thereby providing a rigid connection for the extension tube. When the extension tube is removed the t1p may be replaced upon the nozzle. In the event that it is not replaced, the jet opening 41 will nevertheless function in its normal manner, as distinguished from other types of air guns, where the removable tip provides the air jet opening, and removal of the tip therefore, leaves a large and inefiective exit passage at'the end of the nozzle.

I have illustrated and described a preferred and satisfactory embodiment of the invention, but it will be understood that changes may be made therein, within the spirit and scope thereot. as defined in the appended claims.

What is claimed is:

1. A safety air jet gun comprising in combination, a body member having an inlet and an outlet; an outwardly diverging surface, formed on said outlet; a nozzle member having an axial air et passage therethrough; peripherally-disposed ribs on said nozzle member for centering said nozzle member within said body member; an outwardly diverging surface on said nozzle member adapted to cooperate with said outwardly diverging surface on said body member to form therewith an outwardly diverging annular slot; an annular air chamber between said slot and said ribs; a valve between said inlet and said nozzle including a plunger normally moved to closed position by the air under pressure supplied to the inlet of said body member; and a removable plu within said body member having means for guiding said plunger and of a diameter to facilitate removal of said plunger.

2. A safety air jet gun comprising in combination, a body member having an inlet and an outlet; an outwardly diverging surface formed on said outlet; a nozzle member having an axial air Jet passage therethrough; radially-disposed airdirecting fins mounted Within said body member adjacent said outlet for centering said nozzle member within said body member; an outwardly diverging surface on said nozzle means adapted to cooperate with said outwardly diverging surface on said body member to form therewith an outwardly diverging annular slot; an annular air chamber between said slot and said fins; a valve between said inlet and said nozzle including a plunger normally moved to closed position by the air under pressure supplied to the inlet of said body member; and a removable plug within said body member having means for guiding said plunger and of a diameter to facilitate removal of said plunger.

HARRY A. YATES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

